Progressive multiple spindle gear shaping machine



E. w. MILLER? Feb. 5,1935.

PROGRESSIVE MULTIPLE SPINDLE GEAR SHAPING MACHINE originalriled dan. 26,1928 7 Sheets-Sheet 1 Ilvlnlln. l

7.17.6 Le 'bo Feb. 5, 1935. E. w. MILLER 1,990,240'

- PROGRESSIVE MULTIPLE SPINDLE GEAR SHAPING-MACHINE O rigial Filed Jan.26, 1928 '7 Sheets-Sheet 2 9 Feb. 5, 1935.

E. w. MILLER 1,990,240

PROGRESSIVE .MULTIPLE SPINDLE GEARYSHAPING MACHINE 7 Sheets-Sheet 3Original Filed Jan. 26, 1928 E. w. MILLER PROGRESSIVE MULTIPLE SPINDLEGER SHA-PING MACHINE I EMI eoy 12, '1o

E, W. MILLER Feb. 5, 1935.

PROGRESSIVE MULTPLE SPINDLE GEAR SHAPING MACHNE original Filed Jan.26,1928 rr sheets-sheet 5 Feb. 5, 1935. E. w. MlLLER 1,990,240

PROGRESSIVE MULTIPLE SPINDLE GEAR SHAPING MACHINE Original Filed Jan.26, 1928 ,'7 Sheets-Sheet 6 Feb. 5, 1935. E, W, M|| ER 159905240PROGRESSIVE MULTIPLE SPINDLE GEAR .SHAPING MACHINE Original Filed Jan.26, `1928 7 SheetS-Sheet' @Yiwu Patented Feb. .5, 1.935

PROGRESSIVE MULTIPLE SPINDLE GEAR sHAPING MACHINE Edward W. Miller,Springfield, Vt., assignor to The Fellows Gear Shaper Company,Springfield, Vt., a corporation of Vermont Continuation of applicationSerial No.y 249,569, 4January 26, 1928. This application June 2,

19.34, Serial No. 729,134

sz claims); (c1. :ao-9)' The present invention relates to gear shapingmachines of the type using a cutter having a series of radiallyprojecting teeth arranged concentrically about an axis, the cuttingedges of which are at one end of the cutter, and in which the generationand cutting of gear teeth in the work is effected byproduc/ingjimultaneous rotation-off-fthel cutter and workiaboutdifferent axes and endwise relative reciprocation between the cutter andwork; the cutter then acting in the manner of a planing or shaping tool.The object of the invention is to increase the output of completed gearspier machine' and is accomplished by providing a plurality of Workspindles, on each of which a gear blank to be cut is mounted, a numberof said,gear blanks being acted upon simultaneously vby the cutter andallv of them being cut progressively to increasing depth byA successiveparts of the cutter. As a practical measure, the spindles are arrangedso that at any given time one of them is approximately in position forremoval of the finished` Work and substitution of. a new gear blank,While all the others are inposition to hold their work pieces in cuttingrelation to the cutter.

The nature and principles of the invention are more fully explained inthe following specification in connection with a detailed description ofcertain specific embodiments of such principles shown in the draw-ingsfurnished herewith.

In the drawings,-

Fig. l is a vertical central section through the cutting head and workholder of the machine on an offset plane, the position of which isindicated by the line 1-1 in Fig."2;

Fig. 2 is a horizontal section on an offset plane indicated by the line2-2 of Fig. 1;

Fig. 3 is a fragmentary elevation showing the gear train represented insection in Fig. 2;

Fig. y4 is a horizontal section taken approximately on line 4-4 of Figs.1 and 5.`

Fig. 5 is a vertical section taken on -line 5--5 of Fig. 4;

Fig. 6 is'a fragmentary section on a larger scale taken through the axisof one of the vwork spindles;

Fig. '1 is a fragmentary elevation of part of the means for affordingradial relief between the cutter and work during the non-cuttingstrokes;

y Fig. 8 is an elevation ofthe parts shown inV Fig. 7;

Fig. 9 is a vertical sectionvof part of the mechanism for controllingthe rotation of the work spindles, the plane of such section beingindicated by line 9-9 in Figs. 2 and 10;

Fig. 10 is a section on line 10-10 of Fig. 9; Fig. 11 is a diagrammaticplan view illustrating the character of the generating and cuttinglaction performed by this machine:

Fig. 12 is a horizontal section and partial plan view of a machinediffering in'some particulars from that shown in the preceding drawingsfor doing the same lwork;

Fig. 13 is in part an elevation of the modified machine shown in Fig. 12and in part a vertical section on line 13-13 of said iigure;

Fig. 14 is a diagrammatic plan View similar to Fig. 11 showing theapplication of a specifically different cutter for doing the same work;

Fig. 15 is a fragmentary section of the cut-ter and one of the workpieces shown in Fig. 15 taken on line 15-15 of the latter figure.

Like reference characters designate the same parts wherever they occurin all the figures.

Before describing in detail the machine here shown, I will explain withreference to Fig. v11 the character of the work done by th machine. Asmentioned in the introductory statement of this specification, it is acutting operation performed simultaneously on a number of work piecesand a progressive action is performed in turn upon each. Forthis purposea number of Work spindles 1, 2,) 3, 4, 5, etc. are provided spacedequidistantly from and equally around al common center 6, and allparallel to one-another. The cutter consists'of a seriesofcuttingelements or segments 8, 9, 10, 11 and l2, each having teeth similar tothe teeth, or portions thereof, of a gear. Said elements or segments aresecured to a holder ring 13 in series on the arc of a circle concentricwith the axis 6 and their teeth are spaced equally apart with referenceto a. common pitch circle concentric with this axis. In the particularembodiment here shown, the teeth of the cutting elements correspond tothe teeth of an internal gear, except in the particulars presentlypointed out,A but the invention is not limited to the cutter of theinternal gear type as distinguished fromA one of the external vgeartype, as is later explained.

The teeth of segment 8 are short and lie outside of the common pitchcircle of the segments. They correspond to .the base or root portions ofinternal gear teeth and have onlysuch height same amount; those of thecutter segmentv 11 have approximately equally greater height than thoseof cutter 10; and those of the last cutter segment 12 have the fullheight, width and outline necessary for generating and cutting teeth ofthe finished length and form in the Work.

The cutter segments do not occupy a `complete circumference, but they,and the housing in which the cutter is held, are interrupted at one sideto provide an open space of width suflicient to give access of a workmanto the spindle traversing such space so that he may remove a finishedgear from the spindle and substitute a gear blank in place of it.

It may be assumed for the purpose of this xplanationthat the spindlesrevolve bodily about the center 6, in the direction indicated by thearrows in Fig. 11, and that each spindle is rotated about its own axisat a speed which causes the gear blank thereon to roll on its pitchcircle along the pitch circle on which the cutter teeth are arranged,in'themanne'r of a planetl pinion rolling in mesh with an internal sungear. Meanwhile the cutter is reciprocated rapidly along the line of theaxis 6, and with each stroke in one direction planes of! those parts ofall of the gear blanks (work pieces) which are in position to be soacted upon. l

Each cutter segmentis at least equal in pitch circle length to the pitchcircle circumference of the gear blanks and has at least as many teethas are to be cut in the work. Thus each blank, in making the circuit ofthe cutter, is cut throughout its entire circumference to a greaterdepth by each successive cutting segment. There may be as many suchsegments as the number of successive cuts which are determined upon as fnecessary to finish the gear, and the complete cutter is made of asufficiently large diameter, in proportion to the diameter of the gearblanks, to accommodate the number of segments thus determined. I havefound that for some classes of work ve cuts are enough to make thefinished gear without 'taking too heavy a cut at ,any stage, and haveshown that number here; but'it is to be understood that I may provideless or more than that number according to circumstances.

'I'he numberof work spindles is determined by the speed of cuttingcarried out by the machine and the ability of the attendant to removeand replace gears and blanks on the exposed spindle. The desideratum isto present finished work pieces as fast as a competent attendant canremove them and substitute blanks continuously throughout the workingtime without excessive fatigue. I have found it entirely feasible withthe use of ve spindles as here shown .to operate the machine at speeds,as to both cutting and generating travel, such that a finished gear ofthe size of the larget gear in the standard automobile transmission ispresented at the discharge point every thirty seconds. Smallergears maybe cut more rapidly; and so may gears of any size with the provision ofa larger number of spindles, other things being equal. v

The cutter is carried by a cutter spindle 14 which ts slidingly in anupright guide 15 and has a head 14a of approximately the same diameteras the cutter, which forms the housing previously mentioned, asd in turnis fitted to slide in a guide Y16. The guides here mentioned are partsof a base or framework of any suitable construction. and form, whichsupports the work drum, later' described, and other moving andstationary parts. In Fig. 1, which shows the featuresjust described, thecutter as a whole is indicatedfby the same reference character 8previouslyA used to denote one of the segments of the cutter.

For reciprocating the cutter I provide a crank arm 17 on a main shaft 18which 4is driven by-a belt pulley 19 or other suitable means. Crank arm17 has a radial guideway in which is adjustably mounted a crank pin 20coupled to a connecting rod 21, which rod is in turn coupled to a lever22 arranged to oscillate on a pivot 23 secured f to the side of theguide 15.. One arm of the lever 22 extends into the hollow interior ofthe tubular cutter spindle 14 and is connected therewith by a. link 24.This link is connected to lever 22 by a coupling pin 25 and to thecutter spindle by a wrist pin 26, the ends of which are seated in asleeve 27, fitted removably in the spindle and seated at its inner endagainst a shoulder 28 in the latter and confined at its outer end by aplate 29 overlapping the adjacent end of the spindle and detachablysecured thereto by bolts or other suitable means ofl well knowncharacter.

lThe cutter is shown in Fig. `1 as arranged to cut a gear 30 forming apart of an integral co1,

lection of coaxial gears such as are used on the countershaft of thestandard automobile 'transmission.. In order to adjust the position ofthe cutter for the other gears of the samecollection,

i or any others which have to be placed in a different plane from thatof the gear 30, the connecting rod 21 is coupled to lever22 by a sleeve31 fitted ,to slide on the threaded part 32 of such rod and havingexternal pivot studs received in bearings in the forke'd end 33 of lever22. Adjusting nuts 34 meshing with the'threaded part 32 secure thesleeve 31 in different positions. Adjustment of the length of stroke'ofthe cutter is effected by setting the crank pin in the guideway vdrum 35fitted to turn in a guide bearing 36 in the machine base, co-axial withthe cutter head 14a, and tted with a worm gear 37 which rests on ahorizontal surface 38 adjacent to the bearing 36. It is driven by a worm39 meshing with the worm gear 37 and carried by a shaft 40,v whichlatter is driven from the main shaft 18 through a gear train 41, 42, 43and 44 y(Figs. 2 and 3). The intermediate gears -42 and 43 of this trainare secured on a shaft 45 by which accessory parts of the machine aredriven. Gearsl 41 and42, which drive the shaft 45, are of equal size sothat the shaft 45 -is turned at the same an gular speed as shaft 18.changeable gears whereby different speeds of rotation may be given tothe work carrying drum 35.

The work spindle indicated at 5 in Fig. 1 is shown in section in Fig. 1andlikewise shown on a larger scale in Fig. 6. All the Work spindles arealike, and a description of this one will suilice for all. It is, seatedto rotate in a bearing 46 forming partJ of an apron or carrier laterde-A scribed, and having a flange-47 which overlaps The cutter head orhousing Gears 43 and 44 are" of the spindle below the bearing sleeve 46,preferably keyed to the spindle, and held thereon by va nut 49. A washeror distance collar 50 is located between the gear 48 and the end ofbearing 46. Gear 48 meshes with a large internal gear 51 and serves torotate the spindle about its own4 axis while being revolved about theaxis of the cutter head by the holder 35. The teeth of the gears 48 andinternal gear 51 are complementally l tapered to a slight degree, asshown in an ex- Cil aggerated way in the drawings in ord-er to'eliminatebacklash, and the collars or distance plates 50 are made of suchthickness as to position the gears 48 where they will engage theinternal gear with a minimum of backlash but without binding.

If the teeth wear thin in course of time, the distance plate may be madethinner in proportion.

In 'the simplest form of the machine, that designed to' cut-gears ofonly one diameter, the spindle carried gears 48 may be of exactly thesame pitchdiameter as vthe gears to be cut and the internal gear 51 maybe of exactly the same pitch diameter as the cutter. In'that case thegear 51 may be fastened stationary tothe machine vbase and it will giveexactly the required rotary movement to the work pieces. But it ispreferable to make the machine adjustable to work of different sizes,and it is generally preferable in the interest of accuracy to make therotation controlling gear 48 substantially larger than the work piece.Therefore, to suit these conditions and at the same time rotate the workabout its own axis in the proper ratio, I have made the large controlgear 51 rotatable and provided a changeable gear train for rotating it.

The' gear 5l is connected `with an external worm gear 52 and is fittedto a bearing in a ledge r'53 in the machine base on which the worm gear52 rests. A worm 54 meshes with and drives the worm gear 52 andis drivenfrom the worm shaft 40 by the following mechanism, shown in Figs. 2, 9and 10. 'I'he extremity 40a of shaft 40 is con- Anected by a coupling 55witha shaft 56, on the extremity of which is a gear 57 meshing with agear 58 on a shaft 59 which is in alinement with the shaft 60 carryingthe worm 54. Shaft 59 carries a bevel pinion 61 meshing with twoplanetary bevel pinions 62 and 63 carried on a transverse pivot 64 in ahousing 65 which is mounted toy rotate about the axis of shaft 59,having hubs 66 tted to turn on the bushings 6,'7 and 68 in which theshaft 59 and a shaft '70 alined therewith have their bearings. Shaft'70carries a bevel pinion '71 which also is in mesh with the planet bevelpinionsv621and 63 at the opposite side of the latter from the pinion 61.Shaft'70 is connected with the worm shaft 60 by a coupling '72.

The housing carries an external gear element '73 with which meshes aworm '74 on a shaft '75. The latter shaft is connected by gears '76 and'7'7 with a shaft 'I8 carrying a helical gear '79 in mesh with a helicalgear 80,on shaft 56. This mechanism provides two gear trains throughwhich in 'cooperation the shaft 40 drives the worm 54. One of such geartrains includes the bevel pinion assemblage, which forms a differentialgearing driving the shaft '70 at a, ratio to the speed of the shaft 59determined by the rate of rotation given to the housing 65.. The gearpairs 5'7, 58, and also '76,77 are changeable gears, by the properselection of which any desired speed `of rotation may be given to theworm 54. For

control gear 51 may be lgiven by the change gears 5'7 and 58 alonewithout any movement of the diierential gear housing, and for such casesthe differential gearing is unnecessary; but the latter makes possible amore minute variation or change in the diiferent speeds which` may begiven to the control gear 51,- enabling it to be driven atcertain speedswhich could not be obtainedby any single pair of change gears on theshafts-56 and 59.

In adjusting the machine to cut gears of a different pitch diameter4than the work piece 30, the cutter holder 13 is removed from the cutterhead 14a and a cutter of appropriately different diameter issubstituted. The cutter holderis fitted to the head in the mannerclearly shown in Fig.

1 and detachably secured thereto by screws or otherwell knownappropriate fasteningmeansl lnot necessary to be shown here.

clamped down by a nut 86 screwed on the end of the shank.

Relief of the work after each cutting stroke to avoid rubbing of thecutting edges of the cutter teeth on the work'during the return strokesis aiforded by the means which I will now describe. The bearingsleeve 46of each spindle is formed as part of, or is secured to, an apron orholder 8'7 having bearing hubs 88-fitted to a pivot pin 89 mounted in aboss 90 attached to or integral with the drum 35; such boss, pivot, andhubs for the apron of spindle 2 being shown in Fig. l. The aprons havearms 91 carrying rolls 92 so arranged as to bear on different sides of abar 93 located and movable endwise in the axis of the drum. Said bar isso movable in a flxed guide 94 supportedvby the machine base and isreciprocated by the shaft 45, previously described, through. the mediumof a crankpin 95.connected to'said shaft, a connecting rod 96 coupled tothe crank pin, and a rock lever 97 pivoted on a stationary fulcrum 98,and of .which one arm is coupled to the connectingrod.` The opposite armof lever 9'7 is forked at 99 to embrace the lower end of bar 93 andcarries studs 100 entering the groove between collars or shoulders 101on the bar. The upper end of bar 93, which rises between the rolls 92carried bythe several work spindle aprons, serves as a cam, having a lowdwell 102 and a high dwell 103 at each Iside adjacent to the severalrolls 92. When the bar is raised, the rise to y its highdwell 103 movesthe aprons outward and Asimultaneously forces all of the spindlecarryingsleeves into ilrmv engagement with the recessed semi-cylindrical seats104 in the inner side, of thel drum 35. When the bar is lowered, the lowcam part permits the spindles to be moved slightly out of such seats bysprings 105 situated inthe Adrum and acting on the spindle holdingsleeves ring at the end of the cutting stroke after thev cutterhaspassed through the work and the seatand the cutter.

Although the cam part ofv the bar 93 is shown here as having fiat sidesequal in number to the spindles, which requires the bar to be rotated byand with the spindle aprons'in their revolution, it will be understoodthat this part of the bar may equally well be made with cylindricalsurfaces.

The teeth of the cutter are backed off on the sides and outer ends toafford cutting clearance, causing contact with the work pieces to occuronly at the cutting edges in the larger ends of the teeth; and aresharpened at need by grinding away the end faces in which these cuttingedges lie. The effect of thus grinding the teethis to make themnarrower, and in order to enable them to continue the cutting of teethhaving a given width in the work, after being thus narrowed, the centerdistance between cutter and work pieces remaining the same, I provide ameans for oscillating the cutter head slightly about its axis inalternate directions. This' means is partly shown in Fig. l and morefully in Figs. 4 and 5.

A bevel gear 106 on shaft 45 meshes with a bevel gear 107 on an uprightshaft 108 which carries a cam 109. Such cam acts on a lever 110 througha roll 111 mounted on the latter and pressed against the cam by a stiffspring 112 which reacts on the machine frame. Lever 110 turns on a pivotrod 113, mounted in brackets 114 on the machine frame, and carries armsorlugs 115 in which is mounted a coupling pin 116. 'I'his pin isparallel in all of its positions to the reciprocating travel of thecutter and is embraced by an eye 117 formed on a stud 118- which isseated -in a radial socket 119 in the cutter head and is movable endwisewith a close sliding fit therein. The coupling pin 116 is long enough tomaintain engagement with the eye 117 throughout the whole reciprocatingmovement of the cutter head in anyz' location where such reciprocationmay take place, and thus constantly maintains a connection fortransmitting oscillation from lever 110 to the cutter head. i

Cam 109 has a-high dwell at 120 and a low dwell at 121 and is so timedwith the cutter reciprocating crank, being rotated at half the angularspeed of the latter, that these high andlow dwells alternately controlthe cutter head during alternate cutting strokes. Preferably also thecam ,has intermediate dwells 122 and 123 at opposite sides between thehigh and low dwells for f positioning the cutter teeth clear of theteeth in the work piece, thus affording relief yof the cutter additionalto that given by the backing off` movement of the work spindles, duringthe noncutting the angular movement required when the cutter teeth havebeen reduced to theirleast thickness at the end of their useful lifeafter repeated sharpenings. Hence n order to meet the conditions fromthe beginning of the use of the cutter. when its teeth may have the fullwidth, through intermediate stages when its teeth become narrower, Iprovide an adjustment consisting of a screw 128 mounted ina part of themachine frame where it serves as a stop in Athe path of the lever 110,limiting the movement of the lever toward the axis of the cam. By thismeans the lever may be wholly restrained from movement or permitted amovement of any extent up to the limits of the cam.

It will bev noted that the coupling pin 116 is a guiding element whichpositively prevents any rotational or oscillative movement of the cutterhead except such movement of that character as is imparted to it by thecam 109. Thus the' cutter is constrained to travel in a definite fixedpath when making its cutting strokes, and such oscillative movements asarev imparted toit for the purpose described take place only before andafter the successive cutting strokes. No reliance is placed on thecutter reciprocating means (i. e.,

Alever 22, link 24 and wrist pins 25` and 26)' for thus guiding thecutter, and no looseness need be provided between these parts in orderto permit of the oscillative movement asrequired, for the` sleeve 27through `which reciprocation is imparted to the cutter is rotatablewithin the cutter spindle oscillating the cutter head in bothdirections, in-

stead of a. spring for moving it in one direction,

may be used in place of the specific mechanism here shown and justdescribed without departing from the invention and the protection whichI claim. But that here shown affords a very simple means for giving thedesired movement with the necessary capacity for adjustment. `I havefound that with the use of a spring 112 of sufficient stiffness, thecutter is held up to the work in a vwholly satisfactory manner. Thiscapacity for lateral movement avoids necessity of changing the distancebetween the axis of the work spindles andv the axis of the cutter, inother words, the center distance between the several work pieces and thecutter, to compensate for narrowing of the teeth, which would requirecomplicated means to achieve simultaneously with a plurality of workspindles and would be diflicult to accomplish accurately.

Although sharpening of the cutter teeth also,

shortens their length, due to the clearance bevel of their outer endfaces, such shortening does not necessitate any change in the centerdistance between the cutter and work spindles, because the cutter teethare made with suicient excess length originally to allow xfor shorteningin this manner.

'The teeth of cutters used in gear cutting machines in standard practiceare always made longer than the teeth of gears conjugate to the workpieces, in order to cut tooth spaces amply deep to leave clearance forthe mating gear teeth. This practice is followed in the final orfinishing segment 12 of the present cutter. The depth of tooth spaces ina gear isa value which may be varied within wide limits withoutaffecting the accuracy or sacrificing essential strength of the gearteeth; and the shortening of the teeth of my cutter at the end of itsuseful life is less than such permissible variation. As the teeth of allthe segments of my cutter are bevelled to the same degree and groundaway-substantially equally in sharpdescribed, both deepen and widen suchspaces as ening, the increment of tooth length between.

successive segments remains substantially the same at all times.

A shield 129 is arranged over the work carrying drum, having aperturesfor the spindles, to deiiect chips and oil away from the interior of thedrum and into the runways provided for taking care of these matters.Suitable housings, casings, etc. are provided elsewhere to guard andprotect the gears and certain other moving parts,

as plainly enough shown in the drawings, or otherwise. I have notattempted to describe in detail these accessories and the supportingstructure, aslthese parts may be embodied in many diverse forms allwithin the skill of the machine designer. And moreover, the operatingmechanisms and parts may be variously modified in construction andarrangement within the scope of the invention.

I have shown in Figs. 12 and 13 one possible different arrangement inmeans for revolving and rotatingthe work spindles. carryingv drum andindividual spindle holders are substantially the same as previouslydescribed, but instead of providing a large gear 51 for rotating thespindles, I provide in connection with each spindle a worm 130 carriedby suitable supporting means so as to mesh with a worm gear 131corresponding to the gear 48 pre:A

viously described. With each worm 130 is combined a bevel pinion 132 inmesh with a bevel gear 133 turning about a central` bearing, andconnected with a bevel gear 134 in mesh with a driving .pinion 135. Thelatter pinion is secured to a shaft 136 which also carries a sprocketwheel 137 and the sprocket is driven by a chain 138 from a sprocket onthe shaft 139 which corresponds to the shaft 70 of the previouslydescribed machine. The shaft 139 is controlled as to its speed vby thechangeable speed gearing shown in detail in Figs. 9 and 10, and itdrives the gears 131 through the intermediate gear train just described,at the speed necessary to roll the work pieces in Athe required mannerpast the cutter teeth. The worms here shown, having a small angle oflead, have the advantage of locking the In the introductory part of thisspecification' I described in detail one form of cutter suitable for theuses of my'new invention. I wish to make it understood, however, that Imay use other cutters of substantially different character. Thus inFigs. 14 and 15 I have shown a cutter in which the teeth are arranged asin an external gear rather than an internal gear and in which, moreover,the individual teeth are somewhat different in character as to all thesections of the cutter eimept the last section. Thus in the' section 8a,the teeth are not only short, but are thin also, whereas in thecorresponding section 8 of the cutter shown in Fig. 11 they correspondto the roots of full width teeth. In section 9a. the teeth are bothlonger and wider; inlsection 10a they are still longer and wider; insection 11a yet longer and wider; and in section 12a they have the-fulllength, width and form necessary to shape the teeth in the work' totheprescribed finished size and form. Hence the teeth of successivesections, instead of merely deepening the tooth spaces in the work, asis done in the cutter first Here the work well. The form of tooth shownin Fig. 14may be employed with the internal gear type of cutter amachine of the character here shown, the work spindles are necessarilyarranged outside of the circumference of the cutter, and the movementgiven them for relief must be outward instead of inward with respect tothe axis of the cutter. In other respects the machine using the externalcutter is or may be substantially identical with that using the internalcutter; and it is equivalent in its differences. Fig. 15 showsillustratively one of the possible modes in .which the external cuttermay be applied to the cutter spindle; the section of the cutter beingattached toa holder 140 fitted externally to the spindle and clampedagainst a shoulder 141 thereon by a nut 142.

It will be apparent that my new machinei in comparisonwith. the singlespindle gear shaping machines, speed of cutter travel and amount ofmetal taken off at each cut being equal, is` capable of turning out workfaster, proportionally to the number of spindles in cutting positions,v'(in this illustration four times as fast) and; that in addi--rnachines, -operating on the Fellows shaping rprinciple,require aprogressive depth feed in adldition to the generative rotation. Such,depth feed can be performed either as a step independent of thegenerative travel, or simultaneously with such generative travel.` Ineither case it `consumes time additional to'that required for thecomplete generation of a gear after the cutter has been fed to fulldepth. Furthermore, when the depthv and rotary feeds are combined in theprior art machines, a greater load is imposed on the cutter during theperformance of the depth feed than afterwards, which it is desirable toavoid. y f

This invention affords a means by which the -gear blank may be broughtdirectly into pitch circle relationship with the cutter teeth forimmediate commencement of tooth generation without preliminary depthfeed; and .this would be equally the case if the cutter were providedwith only the nishing series of teeth or with a smaller number ofpreliminary teeth than here shown. The last series of teeth, or the nextto the last series, could be brought directly into engagement with ,theuncut blank and would' perform satisfactory service if the rst one orlmore series of teeth (8, 9, etc.) were omitted. In this aspect of theinvention it is immaterial whether the cutter is provided with many orfew preliminary roughing setsof teeth, or with none at all. Theimportance of the large number of progressiveroughing teeth here shownfollows from the better distribution of duty and wear among thedifferent sets of teeth, the ability of the cutter tool to acteffectively and progressively onra large number of gear blanks at thesame time, andthe more rapid production l.of finished gears. y

Although the space occupied by the collection of work spindles andcutter head is somewhat y 'ns I is not larger or more costly in at allnearly equal proportion to the increased number of spindles andincreased output capacity. At the same time all'the advantages due tofinishing the gear in a plurality of cuts are secured without time loss.

vThe last section of the cutter may, if desired,

be made to take a very light finishing cut for the greatest accuracy andbest finish.

It is to be understood that the foregoing description of a specificmachine and modifications thereof is illustrative of the inventionrather than a limitation to the specific construction and arc rangementof the machine and parts thereof so described. Evidently many variationsin coni Referring to the cutter, the parts thereof whichl I havedescribed as cutting elements or segments are, more broadly, groups ofteeth which, in the broad aspect of the invention need not be made asstructurally separate segments but may be integral parts of the Wholecutter. `On the other hand, each group of teeth may be composed of Vmore than one structurally separate segment or piece. l Every tooth ofthe cutter is in effect a distinct cutting member, having edges disposedso asto axis of the orbit in which the gears travel. That is, the phaseof the invention consisting of the combination of such a series ofcutting members or'units with a number of planetary work spindles andthe appropriatel operating means, is a useful machine for rapidlyfinishing in a desired manner gears which have been previously cut inanother machine. By means of the multiplicity of spindles, operatingsuccessively invconnection with the same cutting units, the gears may bebrought t0 finished character as rapidly as it is possible for anoperato-r to remove them and apply new work pieces to the work spindlesarriving at the interrupted side of the series.

What I claim and desire to secure by- Letters Patent is:

l. A multiple gear shaping machine comprising a shaping 'cutter having acircular series of v1,9`9o,24o n inthe manner of the teeth of a gear`Wheel, suc--V shaped to cut to respectively increasing de th in cessivegroups of teeth in the series thereofxieing the work pieces, means' forgiving a simulta ecus rolling movement between the cutter and aplurality of work pieces similar to that between a un gear and aplurality of planet pinions, and means for effecting relative axialreciprocative cutting movements between the cutter and work pieces.

`3. A plurality gear shaping machine compri: lng a cutter having aseries of cutting teeth arranged and equally spaced side by side along agiven pitch line, the number of such teeth being a multiple of the teethto be cut in the work and being arrangedjn groups or sections, each suchgroup` containing a number of teeth as great as the number to be cut inthe work and those of'each successive group being longer than those ofthe preceding group; combined with means for effecting simultaneous andprogressive generating trav'erse along said pitch line* between saidcutter and a plurality of duplicate work pieces, and means for effectingrelative cutting traverse between the cutter and work pieces.

4. A plural gear generating machine comprising a cutter having adiameter at least twice as great as the diameter of the gear to be cutand provided with cutting teeth in an arrangement corresponding to thatof the teeth of a gear wheel, means for effecting simultaneous planetarymovement of a. plurality of gear blanks in pitch circle relation to thecutter as to a sun gear, and meansv for reciprocating the cutteraxially, the cutter being interrupted inV a part of its circumference toform a space permitting removal of nished gears and substitution of gearblanks in such space.

5. IA plural gear generating machine compristransit across ing a cutterhaving a diameter at least twiceas great as`l the diameter of the gearto be cut and provided with cutting teeth in an arrangementcorresponding to that of the teeth of a gear wheel, means for effectingsimultaneous planetary movement of a plurality of gear blanks in pitch circle relation to the cutter as to a sun gear, and-means forreciprocating the cutter axially, the cutter having a set of teeth of aheight to cut only a fraction of the predetermined depth of the teeth tobe formed in the work, and a second set of teeth of a height sufiicientto cut into the work to an-` other fraction of such depth, the number ofteeth in each of said sets being at least as great as the number ofteeth to be cut in the work.

6. Amultiple gear shaper having a generating cutter Vwith teeth arrangedside by side along a given pitch lineand exceeding by a multiplegreaterthan one the number of teeth to be cut in a single work piece,said teeth in successive parts of the cutter being of progressivelyincreasing height, means for progressively rolling a series of workpieces in succession along the pitchline of said cutter, and means foreffecting relative axial reciprocative movement between the cutter andsaid Work pieces.

7. A gearl generating machine comprising a planing cutter having teetharranged in the manner of the teeth of a gear Wheel and having adiameter exceeding that of the gear to be cut, a work carrier rotatablecoaxially with said cutter, a plurality of work spindles mounted insaidcarrier equidistant from Athe axis thereof and distributed aboutlsaidaxis, means for rotating said carrier, and means for rotating theseveral spindles about their own axes in the course of such rotation ofthe carrier.

8. A gear generating machine comprising a planing cutter having teetharrangedin the manner of the teeth of a gear wheel and having a diameterexceeding that of the gearto be cut, a work carrier rotatable coaxiallywith said cutter, a plurality of work spindles mounted in-said carrierequidistant from the axis thereof and distributed about said axis, gearwheels connected with the several spindles, and a control gear by whichall of said spindle gears are rotated during the rotative movement ofthe carrier.

9. A gear generating machine comprising a planing cutter having teetharranged in the manner of the teeth of a. gear Wheel and having adiameter exceeding-that of the gears to be cut, a work carrier rotatablecoaxially with said cutter, a plurality of work spindles mounted in saidcarrier equidistant from the axis thereof and distributed about saidaxis, means for rotating the work carrier, gear wheels connected withthe several spindles, a control gear coaxial with said Work carrier indriving cooperation with the spindle gear wheels, and means for rotatingsaid control gear simultaneously with the work carrier at lsuch a speedand in such direction as to effect planetary gear mesh between workpieces carried by the spindles and the-cutter.

10. A gear generating machine comprising an axially movable planingcutter having teeth arranged similarly to the teethof a gear wheel withcutting edges in a plane transverse to the axis of the cutter, thenumber of said teeth-being a multiple greater than one of the number ofteeth to be cut in each work piece, a work carrier mounted to rotateabout an axis in line with the axis of the cutter, a plurality of workspindles carried by said carjrier spaced about the axis thereof equi,-

distantly from such axis and in positionl to hold work pieces in cuttingrelationship tothe cutter, means for reciprocating the cutter, meansforI simultaneously rotating the work carrier and also rotating thespindles about theirown axes, and means for oscillating, the cutterabout its axis between successive cutting strokes thereof in oppositedirections to an extent sufficient to cause action of the cutter-teethalternately at opposite sides of the spaces in the work pieces whereinthe cutter teeth project.

11. In a machine of the \character described, a cutter head mountedwith' capacity for-oscillative movements about its axis andreciprocation in the directions cf its axis, mechanism forsoreciproeating the cutter head, a bar extending parallel to the axis'ofthe cutterfhead and vmounted to oscillate about a parallel axis, meansfor so' oscillatingsaid bar, and acoupling' between the bar and cutterhead having sliding engagement with the bar longitudinally thereof andwith the cutter head radiallyof the latter.

` 12. AIn a machine of the character described, a reciprocative cutterhead mounted with provisions for oscillative movement about an axisextending'in the same direction as its path of reciprocation, means forso reciprocating the cutter head, a cam driven in timed relationshipwith the head reciprocating means, an'arm controlled by said 'cam andcaused thereby to swing back and forth about an axis parallel tothat ofthe cutter head, a bar parallel to said axis connected with lsaid Aarmand oscillated thereby about the axis thereof, and a coupling carried bythe cutter head having sliding engagement with the bar and formed totransmit the oscillative movements thereof to the cutter head.

13. In a machine of the character described, a

for oscillation about an axis extending in the same direction as itspath' of reciprocation, means for so reciprocating the cutter head, acam driven in time with the head reciprocating means having.reclprocative cutter head mounted with capacity high and low portions,a lever engaged with the cam, a spring bearing on the lever for pressingit against said cam, an adjustable stop for limiting the movement ofthelever toward' the low part of the cam and regulating the extent of suchmovement, and connections arranged to transmit oscillative movements ofthe lever to the cutterhead.

le. In a gear generating machine, a planing cutter having teeth arrangedsimilarly to the teeth of a gear wheel and having a diameter which is amultiple greater than one of the diameter of the work pieces to be cutthereby, a

work spindle, means for effecting relative .recipro- .l 2O

cative cutting movements between the cutter and work spindle, and meansfor effecting relative rotary generating movements between the cutterand spindle suchv that the work piecey carried by the spindle and thecutter are caused tov roll relatively to one another in the manner ofintermeshing gears; the cutter having its teeth arranged in groups eachcontaining as'many teeth asfthe` teeth of the gear being cut and thoseof each successive `group in the circumference ofthe'cutter being formedto cut to a greater depth in the work than those in the preceding group.

15. A multiple gear cutting machine comprising a planing cutter havingteeth arranged similarly to the teeth of a gear wheel and being of apitch diameter which is a multiple greater'than one of the pitchdiameter of the work, a work carrier rotatable about the axis of thecutter, a plurality of work spindles supported by said carrier spacedabout the axis thereof equidistantly from said axis, means forreciprocating the cutter axially, means for simultaneously yrotating thework carrier. and also rotating the spindles indea pendently about theiraxes, and means'for displacing the spindles from the cutter after eachcutting stroke thereof and holding them so -displaced during the returnstrokes of the cutter.

16. In a gear generating machine of the character set forth, a rotatablework carrying drum,

spindle carrying aprons pivoted to said drum about the axis thereof onparallel axes, arms projecting from several aprons into the mid portionof the drum and terminating beside the axis of the drum, the terminalportions of the several arms being spaced about said axis on differentsides thereof, work spindles supported rotatably in the several apronseach at one side of the pivot of its respective apron adapted to beseated against a complemental abutting surface of the `of such portionswith its movement in the opposite direction; v

17. In a gear generating machine, a cutter, a series of work spindlesarranged to hold work pieces in a relationship to the cutter like thatof planetary gears to a sun gear, means for reciprocatingthe cutter toact simultaneously on a number of work pieces, means for givingap-planeunits.

series.

tary rolling movement toxthe work spindles,

18. A gear cutting machine comprising a series' of cutting members orunits arranged in acircular arc around a given center, a series of workholding spindles arranged around the same center equidistantlytherefrom, means for effecting a simultaneous revoluble and rotationalrolling traverse between said -work spindles and cutting units, andmeans for effecting relative Acutting traverse between them; wherebygears mounted on saidspindles are successively and progressively actedon by the cutting units and desired tooth forms are generated thereby.

19. A plural gear cutting machine comprising a rotatable holder, aplurality of work spindles rotatably mounted in said holder and arrangedcircularly around the axis of rotation of the latter,. a series ofcutting units arranged circularly about the same axis in position to actsimultaneously upon gears mounted ona plurality of the respectivespindles, and means for effecting relative movements of rollinggenerative travel and cutting traverse between said spindles and cutting20. A machine for simultaneously generating the teeth of a plurality ofgears and successively increasing the depth of cut in each gearcomprising a cutter having, a circular series of teeth with cuttingedges in a plane perpendicular tothe axis" of said series, a pluralityof work spindles arranged about said axis and equidistantly therefrom,adapted to carry gears to be out, and means for effecting relativereciprocative cutting travel and rolling generative travel between saidcutter and` all of the spindle-carried work pieces simul- Y taneously;the cutter` teeth being arranged in groups each having a number of teethequal to that of the gears to be cut, and the teeth of each successivegroup being displaced radially from those of the next preceding group bya distance equal to the prescribed steps of depth feed, suchdisplacement as to successive groups being all in the same directionradially. of the axis of the 21. A gear cutting machine comprising arotatable holder,v a plurality of work spindles rotatably mounted insaid holder on parallel axes all at the same distance from therotational axis of the holder, a series of cutting units having outlinescorresponding to those of gear teeth arranged on a pitch line concentricwith the rotational vaxis of the holder and in position to mesh withgears on the respective work spindles, said series of units beinginterrupted at one side to provide a loading station where gear blanksmay be placed on, and finished gears removed from,

spindles upon their arrival at such station, means l for effectingrelative planing traverse between said series of cutting units and thework spindles in the direction of said axis, and means for rotating thework spindles about their own axes simultaneously with the rotation ofthe holder at the same rate as that of a planetary gear rolling in meshwith said series of cutting units.

22. A pluralgearcutting machine comprising a series of cutting unitsarranged on a circular pitch line and extending through the majorpart ofa circumference about the center of such pitch line, being interruptedin a part of such circumference to provide a loading station for theafter mentioned work spindles', said units having cutting edgessubstantially in the plane of said circular pitch line and havingoutlines more or lessv similar to gear teeth, the units at one end ofthev series being relatively short and narrow as compared with standardteeth, and those at the other end of the series having substantially thefull length, width and outlines of standard teeth, while intermediateteeth of the series vary progressively in their dimensions between thetwo extremes; combined with a plurality of workspindles parallel to oneanotherand substantially perpendicular to the plane of said circularpitch line and equidistant-from the center thereof, and

circularly -around the axis of rotation thereof, a

series of cutting units arranged side by side circularly around the sameaxis, each unit consisting of a number of teeth different from the teethof other units and positioned relatively to the work-spindles so thatdifferent units operate at the same time on gear blanks mounted on thedifferent spindles, means for rotating the holder and simultaneouslyimparting a rolling movement to such gear blanks, 'and means foreffecting relative cutting traverse between said spindles and cuttingunits.

24. A plural gear cutting machine comprising a rotatable holder, aplurality of work spindles rotatably mounted in said holder and arrangedcircularly around and parallel to the axis of rotation thereofequidistant from such axis, la series of cutting units arranged side byside circularly around the same axis, each unit consisting of a numberof teeth different from the teeth of other units, but all arranged cnthe same pitch circle and the several units being positioned relativelyto the work spindles so that different units operate at the same time ongear blanks mounted on the diierent spindles, means for rotating thevmeans for traversing said spindles bodily about holder andvsimultaneously imparting a rolling cutting traverse between saidspindles and cutting units in the direction of said axis.

25. A gear shaping machine comprising a shaping cutter having teetharranged on a curved pitch line similarly to the teeth of a gear wheel,throughout less than the whole circumference of the cutter, a spindleadapted to hold the gear blank in pitch line relationship to the teethof said cutter, means for effecting a relative axial cuttingreciprocation between the cutter and work spindle, and means foreffecting simultaneous relative movements of generating -rotation be'-ltween the cutter and work spindle; the number of said cutter teeth beingat least asl great as the number of teeth to be cut in the workpiece,and the space in the circumference of the cutter where teeth are lackingbeing sufiiciently wide to permit placement of a gear blank in pitchline relationship to the cutter without making contact with any tooth,whereby to cause commencement of generative cutting withoutpreliminaryradial depth feed between work and cutter.

26. A" gear shaping machine comprising a work spindle and an axiallyreciprocative cutter spindle aranged on parallel axes, a cutter securedto said cutter spindle having a circumferential series of teeth arrangedin pitch line sequence similarly to the teeth of a gear, but interruptedat one side of the cutter, means for reciprocating the cutter spindle,and means for effecting relative generative rotation between the cutterand work spindle at such rates of speed as to obtain the effect ofrolling mesh between the cutter and a. work piece carried by the workspindle; the interruption between the teeth of the cutter beingsulciently wide to permit placement of a gear blank on the work spindlein pitch line tangency with the cutter, without contacting any of saidcutter teeth, when the work spindle is opposite to such interruption.

27. A gear shaping machine comprising the combination with a cutterspindle and means for reciprocating it, a work spindle adapted to hold agear blank, means for effecting relative generating rotation between thetwo spindles such that a completed work piece carried by the spindle mayroll in mesh with a gear-like `planing cutter, of such a cutter having aseries of gearlike planing teeth arranged on a circular pitch line andbeing interrupted at one side of the cutter through a. width sufficientto admit an uncut blank into pitch line relationship with the cutter;the number of teeth of the cutter being at least as great as the numberof teeth to be formed in the work piece.

28. A multiple spindle gear shaping machine comprising a gear shapingcutter having a circular series of teeth, the number of which is atleast as great as the number of teeth to be cut in the work, and havingalso at one side an open space in which there are no teeth, a pluralityof spindles arranged about the axis of said cutter equidistant therefromand in positions to hold a plurality of work pieces in simultaneouscutting relationship with the cutter, means for reciprocating thecutter, and means for revolving the 'work spindles about said axis withsimultaneous v rotation about their individual axes, said gap lbeingsufficiently wide to receive an uncut gear blank clear of engagementwith any of said teeth upon each work spindle when in position oppositeI' to the gap.

of said cutter equidistantly therefrom and in po- 29. A multiple spindlegear shaping machine comprising a shaping cutter having teeth arrangedon a pitch line surrounding the axis of the cutter similarly to theteeth of a gear, said i teeth being interrupted at one side of thecutter,

a plurality of spindles arranged about the axis axis during all cuttingstrokes, and means for independently rotating said spindles about theirown axes at such speeds as to roll the work pieces carried thereby inmesh withthe cutter teeth;

. the number of cutter teeth being at least as great.

circumference of the work pieces, and the said interruption ofteeth inthe cutter being wide enough to permit placement of an uncut gear blankupon any spindle without making contact with. the cutter teeth when suchspindle comes -oppite to the interruption.

30. A plural gear generating machine compris- 'ing a cutter havingteeth`arranged on a pitch line circumference 'similarly to the teeth ofa gear wheel and having a gap at oneside wherein there are no teeth, thecutter .being more than twice as great in diameter asthe gears tobe cutand having at least twice as many teeth as the number of teeth to be cutin the work pieces, while the said gap is suiilciently wide to admit anuntoothed gear blank into pitch line relationship with the cutterwithout makingcontactwith any teeth, means for effecting simultaneousplanetary and rolling movement of a plurality of gear blanks in pitchcirclerelationto the cutter as to a sun gear, land means forreciprocating the cutter axially.

3l. A gear shaping lmachine including a pla'ning cutter having cuttingteeth disposed correspondingly to the teeth of a gear wheel, means forholding a plurality of work pieces spaced about the axis of said cutterequidistantly therefrom in position to be simultaneously operated on bysaid'cutter, means for effecting relative reciprocation between saidcutter and all of said work pieces simultaneously in the direction ofthe axis of the cutter, and means forgiving said work pieces a planetarytraverse about the axis of the cutter; the cutter being provided withsuch teeth throughout a part only of its circumference `and having aspace at one side devoid of vteeth and wide enough to admit a gear blankinto pitch circle relationship with the cutter without con- K tact ormesh with any of the said teeth.

32. A machine for generating gears by a shaping 'operation withoutradial depth feed which comprises a gear shaper cutter havingv teetharranged in the manner of gear Wheel teeth around less than a completepitch line circumference, a work spindle, means for effecting relativegenerative rolling movementbetween such cutter and work spindle withoutchange of center distance around the pitch line circumference of thecutter from the point where the non-toothed portion of the cutter andthe work spindle are in alinement radially of the cutter axis, means foreffecting relative axial reciprocative cutting movements between thecutter and the work spinl dle, and means for causing a limited relativeoscillative movement about said axis between the cutter and theworkrspindles intermediate successive cutting strokes.

EDWARD W. MIILER.

